U.S. patent number 10,154,503 [Application Number 15/113,337] was granted by the patent office on 2018-12-11 for network node, wireless device, methods therein, computer programs and computer-readable mediums comprising the computer programs, for adapting and adopting, respectively, an allocation of radio resources.
This patent grant is currently assigned to TELEFONAKTIEBOLAGET LM ERICSSON (PUBL). The grantee listed for this patent is Telefonaktiebolaget LM Ericsson (Publ). Invention is credited to Mats Folke, Stefano Sorrentino.
United States Patent |
10,154,503 |
Folke , et al. |
December 11, 2018 |
Network node, wireless device, methods therein, computer programs
and computer-readable mediums comprising the computer programs, for
adapting and adopting, respectively, an allocation of radio
resources
Abstract
A method performed by a network node for adapting an allocation
of radio resources to at least one wireless device for D2D
communications. The at least one wireless device is located in a
cell served by the network node. The network node obtains a
measurement of interference level on allocated D2D radio resources
to the at least one wireless device. The network node also adapts
the allocation of radio resources for D2D communications, based on
the obtained measurement.
Inventors: |
Folke; Mats (Vallingby,
SE), Sorrentino; Stefano (Solna, SE) |
Applicant: |
Name |
City |
State |
Country |
Type |
Telefonaktiebolaget LM Ericsson (Publ) |
Stockholm |
N/A |
SE |
|
|
Assignee: |
TELEFONAKTIEBOLAGET LM ERICSSON
(PUBL) (Stockholm, SE)
|
Family
ID: |
53681741 |
Appl.
No.: |
15/113,337 |
Filed: |
January 27, 2014 |
PCT
Filed: |
January 27, 2014 |
PCT No.: |
PCT/SE2014/050100 |
371(c)(1),(2),(4) Date: |
July 21, 2016 |
PCT
Pub. No.: |
WO2015/112068 |
PCT
Pub. Date: |
July 30, 2015 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20170034834 A1 |
Feb 2, 2017 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W
72/082 (20130101); H04W 8/005 (20130101); H04W
76/14 (20180201); H04W 76/23 (20180201) |
Current International
Class: |
H04W
72/04 (20090101); H04W 72/08 (20090101); H04W
76/14 (20180101); H04W 8/00 (20090101); H04W
76/23 (20180101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
2 665 321 |
|
Nov 2013 |
|
EP |
|
2013028044 |
|
Feb 2013 |
|
WO |
|
2013139041 |
|
Sep 2013 |
|
WO |
|
2014089791 |
|
Jun 2014 |
|
WO |
|
2014115961 |
|
Jul 2014 |
|
WO |
|
Other References
International Search Report and Written Opinion dated Oct. 14, 2014
for International Application Serial No. PCT/SE2014/050100,
International Filing Date--Jan. 27, 2014 consisting of 14-pages.
cited by applicant .
3GPP TSG-RAN WG1 Meeting #74, R1-133494, Barcelona, Spain, Title:
"D2D Communication within Network coverage," Agenda Item: 7.2.8.1.,
Source: Nokia, NSN, Document for Discussion and Decision , Aug.
19-23, 2013 consisting of 4-pages. cited by applicant .
European Search Report dated Sep. 13, 2017 issued in corresponding
European Patent Application No. 4879784.8 consisting of 8-pages.
cited by applicant .
3GPP TR 22.803 V12.2.0, 3rd Generation Partnership Project;
Technical Specification Group Services and System spects;
Feasibility Study for Proximity Services (ProSe), (Release 12),
Jun. 2013 consisting of 32-pages. cited by applicant.
|
Primary Examiner: Pham; Chi H
Assistant Examiner: Hom; Shick C
Attorney, Agent or Firm: Christopher & Weisberg,
P.A.
Claims
The invention claimed is:
1. A method performed by a network node for adapting an allocation
of radio resources to at least one wireless device for
Device-to-Device, D2D, communications, the at least one wireless
device being located in a cell served by the network node, the
method comprising: obtaining a measurement of interference level on
allocated D2D radio resources to the at least one wireless device,
the at least one wireless device being in idle mode, adapting the
allocation of radio resources for D2D communications based on the
obtained measurement, the adapting comprising one of increasing a
number of radio resources available for D2D traffic and reducing
the number of radio resources available for the D2D traffic, the
D2D traffic corresponding to wireless devices located in the cell
being served by the network node that are in idle mode and consume
allocated D2D radio resources, and signalling to one of the at
least one wireless device and a neighbor network node a
reconfiguration of the allocation of radio resources for D2D
communications, which reconfiguration is based on the adapted
allocation of radio resources for D2D communications.
2. The method of claim 1, wherein the measurement comprises one of
(a) an energy level received by one of the network node and the
wireless device on the allocated D2D radio resources, and (b) a
signal detected by one of the network node and by the wireless
device in the allocated D2D radio resources.
3. The method of claim 1, further comprising estimating a fraction
of the allocated D2D radio resources that is utilized for D2D
communication in a radio communications network wherein the network
node and the wireless device operate, and wherein the adapting is
further based on the estimated fraction.
4. The method of claim 1, wherein the obtaining the measurement
comprises one of: measuring an energy level received on a number of
allocated D2D radio resources, and detecting a signal in the
allocated D2D radio resources.
5. The method of claim 1, wherein the obtaining the measurement
comprises one of receiving a report from the wireless device which
report indicates an energy level received by the wireless device on
the allocated D2D radio resources, and a signal detected by the
wireless device in the allocated D2D radio resources.
6. The method of claim 1, wherein the allocation of radio resources
to the at least one wireless device is for scheduling discovery
signals with at least one of the following types: a) Type 1,
wherein radio resources for discovery signal transmission are
allocated on a non-wireless device specific basis, b) Type 2,
wherein radio resources for discovery signal transmission are
allocated on a wireless device specific basis, c) Type 2A, wherein
radio resources for discovery signal transmission are allocated for
each specific transmission instance of discovery signals, and d)
Type 2B, wherein radio resources for discovery signal transmission
are semi-persistently allocated for discovery signal
transmission.
7. A method performed by a wireless device for adopting a
reconfiguration of an allocation of radio resources to the at least
one wireless device for Device-to-Device, D2D, communications, the
wireless device being located in a cell served by a network node,
the method comprising: receiving from the network node the
reconfiguration of the allocation of radio resources for D2D
communications, the reconfiguration being signalled to one of the
wireless device and a neighbor network node and the reconfiguration
being based on an adapted allocation of radio resources for D2D
communication and based on a measurement of interference level on
allocated D2D radio resources to the at least one wireless device
obtained by the network node, the at least one wireless device
being in idle mode, and adopting the received reconfiguration of
the allocation of radio resources for D2D communications, the
received reconfiguration comprising one of increasing a number of
radio resources available for D2D traffic and reducing the number
of radio resources available for the D2D traffic, the D2D traffic
corresponding to wireless devices located in the cell being served
by the network node that are in idle mode and that consume
allocated D2D radio resources.
8. The method of claim 7, wherein the measurement comprises one of
(a) an energy level received by one of the network node and the
wireless device on the allocated D2D radio resources, and (b) a
signal detected by one of the network node and by the wireless
device in the allocated D2D radio resources.
9. The method of claim 7, further comprising determining the
measurement of interference level by one of: measuring an energy
level received on a number of allocated D2D radio resources, and
detecting a signal in the allocated D2D radio resources, and
sending a report comprising the measurement to the network
node.
10. The method of claim 7, wherein the reconfiguration is further
based on a fraction of the allocated D2D radio resources that is
utilized for D2D communication in a radio communications network
wherein the network node and the wireless device operate, the
fraction having been estimated by the network node.
11. The method of claim 7, wherein the allocation of radio
resources to the at least one wireless device is for scheduling
discovery signals with at least one of the following types: a) Type
1, wherein radio resources for discovery signal transmission are
allocated on a non-wireless device specific basis, b) Type 2,
wherein radio resources for discovery signal transmission are
allocated on a wireless device specific basis, c) Type 2A, wherein
radio resources for discovery signal transmission are allocated for
each specific transmission instance of discovery signals, and d)
Type 2B, wherein radio resources for discovery signal transmission
are semi-persistently allocated for discovery signal
transmission.
12. A network node for adapting an allocation of radio resources to
at least one wireless device for Device-to-Device, D2D,
communications, the at least one wireless device being configured
to be located in a cell configured to be served by the network
node, the network node being configured to: obtain a measurement of
interference level on allocated D2D radio resources to the at least
one wireless device, the at least one wireless device being in idle
mode, adapt the allocation of radio resources for D2D
communications based on the obtained measurement, the adapting
comprising one of increasing a number of radio resources available
for D2D traffic and reducing the number of radio resources
available for the D2D traffic, the D2D traffic corresponding to
wireless devices located in the cell being served by the network
node that are in idle mode and that consume allocated D2D radio
resources, and signal to one of the at least one wireless device
and a neighbor network node a reconfiguration of the allocation of
radio resources for D2D communications, which reconfiguration is
based on the adapted allocation of radio resources for D2D
communications.
13. The network node of claim 12, wherein the measurement comprises
one of (a) an energy level configured to be received by one of the
network node and the wireless device on the allocated D2D radio
resources, and (b) a signal configured to be detected by one of the
network node and by the wireless device in the allocated D2D radio
resources.
14. The network node of claim 12, further configured to estimate a
fraction of the allocated D2D radio resources that is utilized for
D2D communication in a radio communications network wherein the
network node and the wireless device are configured to operate, and
wherein the network node is further configured to adapt based on
the estimated fraction.
15. The network node of claim 12, wherein to obtain the measurement
comprises one of: to measure an energy level received on a number
of allocated D2D radio resources, and to detect a signal in the
allocated D2D radio resources.
16. The network node of claim 12, wherein to obtain the measurement
comprises to receive a report from the wireless device which report
indicates one of an energy level received by the wireless device on
the allocated D2D radio resources, and a signal detected by the
wireless device in the allocated D2D radio resources.
17. The network node of claim 12, wherein the allocation of radio
resources to the at least one wireless device is for scheduling
discovery signals with at least one of the following types: a) Type
1, wherein radio resources for discovery signal transmission are
allocated on a non-wireless device specific basis, b) Type 2,
wherein radio resources for discovery signal transmission are
allocated on a wireless device specific basis, c) Type 2A, wherein
radio resources for discovery signal transmission are allocated for
each specific transmission instance of discovery signals, and d)
Type 2B, wherein radio resources for discovery signal transmission
are semi-persistently allocated for discovery signal
transmission.
18. A wireless device for adopting a reconfiguration of an
allocation of radio resources to the at least one wireless device
for Device-to-Device, D2D, communications, the wireless device
being configured to be located in a cell configured to be served by
a network node, the wireless device being configured to: receive
from the network node a reconfiguration of allocation of radio
resources for D2D communications, the reconfiguration being
signalled to one of the wireless device and a neighbor network node
and the reconfiguration being based on an adapted allocation of
radio resources for D2D communication and based on a measurement of
interference level on allocated D2D radio resources to the at least
one wireless device configured to be obtained by the network node,
the at least one wireless device being in idle mode, and adopt the
received reconfiguration of the allocation of radio resources for
D2D communications, the received reconfiguration comprising one of
increasing a number of radio resources available for D2D traffic
and reducing the number of radio resources available for the D2D
traffic, the D2D traffic corresponding to wireless devices located
in the cell being served by the network node that are in idle mode
and that consume allocated D2D radio resources.
19. The wireless device of claim 18, wherein the measurement
comprises one of (a) an energy level configured to be received by
one of the network node and by the wireless device on the allocated
D2D radio resources, and (b) a signal configured to be detected by
one of the network node and by the wireless device in the allocated
D2D radio resources.
20. The wireless device of claim 18, further configured to
determine the measurement of interference level by being configured
to one of: to measure an energy level configured to be received by
the wireless device on a number of allocated D2D radio resources,
and to detect a signal in the allocated D2D radio resources.
21. The wireless device of claim 18, wherein the reconfiguration is
further based on a fraction of the allocated D2D radio resources
that is utilized for D2D communication in a radio communications
network wherein the network node and the wireless device are
configured to operate, the fraction being configured to be
estimated by the network node.
22. The wireless device of claim 18, wherein the allocation of
radio resources to the at least one wireless device is for
scheduling discovery signals with at least one of the following
types: a) Type 1, wherein radio resources for discovery signal
transmission are allocated on a non-wireless device specific basis,
b) Type 2, wherein radio resources for discovery signal
transmission are allocated on a wireless device specific basis, c)
Type 2A, wherein radio resources for discovery signal transmission
are allocated for each specific transmission instance of discovery
signals, and d) Type 2B, wherein radio resources for discovery
signal transmission are semi-persistently allocated for discovery
signal transmission.
Description
TECHNICAL FIELD
The present disclosure relates generally to a network node and
methods therein for adapting an allocation of radio resources to at
least one wireless device for Device-to-Device (D2D)
communications. The present disclosure also relates generally to
the wireless device and methods therein for adopting a
reconfiguration of the allocation of radio resources to the at
least one wireless device for D2D communications. The present
disclosure relates as well to computer programs and
computer-readable storage mediums, having stored thereon the
computer programs to carry out the aforementioned methods.
BACKGROUND
Communication devices such as wireless device are also known as
e.g. User Equipments (UE), mobile terminals, wireless terminals
and/or mobile stations. Terminals are enabled to communicate
wirelessly in a cellular communications network or wireless
communication system, sometimes also referred to as a cellular
radio system or cellular networks. The communication may be
performed e.g. between two wireless devices, between a wireless
device and a regular telephone and/or between a wireless device and
a server via a Radio Access Network (RAN) and possibly one or more
core networks, comprised within the cellular communications
network.
Wireless devices may further be referred to as mobile telephones,
cellular telephones, laptops, or surf plates with wireless
capability, just to mention some further examples. The terminals in
the present context may be, for example, portable, pocket-storable,
hand-held, computer-comprised, or vehicle-mounted mobile devices,
enabled to communicate voice and/or data, via the RAN, with another
entity, such as another terminal or a server.
The cellular communications network covers a geographical area
which is divided into cell areas, wherein each cell area being
served by an access node such as a base station, e.g. a Radio Base
Station (RBS), which sometimes may be referred to as e.g. "eNB",
"eNodeB", "NodeB", "B node", or BTS (Base Transceiver Station),
depending on the technology and terminology used. The base stations
may be of different classes such as e.g. macro eNodeB, home eNodeB
or pico base station, based on transmission power and thereby also
cell size. A cell is the geographical area where radio coverage is
provided by the base station at a base station site. One base
station, situated on the base station site, may serve one or
several cells. Further, each base station may support one or
several communication technologies. The base stations communicate
over the air interface operating on radio frequencies with the
terminals within range of the base stations. In the context of this
disclosure, the expression Downlink (DL) is used for the
transmission path from the base station to the mobile station. The
expression Uplink (UL) is used for the transmission path in the
opposite direction i.e. from the mobile station to the base
station.
In 3.sup.rd Generation Partnership Project (3GPP) Long Term
Evolution (LTE), base stations, which may be referred to as eNodeBs
or even eNBs, may be directly connected to one or more core
networks.
3GPP LTE radio access standard has been written in order to support
high bitrates and low latency both for uplink and downlink traffic.
All data transmission is in LTE controlled by the radio base
station.
D2D communication is a well-known and widely used component of many
existing wireless technologies, including ad hoc and cellular
networks. In D2D communications, wireless devices, such as user
equipments, that are in the proximity of each other discover one
another, in a process referred to as device discovery. They
establish a direct link referred to as D2D bearer establishment,
rather than a link via a base station. The initiation of the
establishment of the D2D link may be made by the radio access
network or by any of the wireless devices of the D2D pair. Examples
of D2D communications include Bluetooth and several variants of the
IEEE 802.11 standards suite such as WiFi Direct. These systems
operate in unlicensed spectrum.
Wireless devices that want to communicate, or even just discover
each other, typically need to transmit various forms of control
signaling. One example of such control signaling is the so-called
signal or discovery signal, which may possibly include a full
message. The signal carries at least carries some form of device
identity and is transmitted by a wireless device that wants to be
discoverable by other wireless devices. Other wireless devices may
scan for the discovery signals. Once they have detected the
discovery signal, they may take the appropriate action, for example
to try to initiate a connection setup with the device transmitting
the discovery message.
Multiple discovery signals from different wireless devices are
multiplexed on the same radio resources in a combination of Time
Division Multiplexing (TDM), Frequency-Division Multiplexing (FDM)
and possibly Code Division Multiplexing (CDM). Even though details
are not agreed yet, it is likely that discovery signals may be
multiplexed on specific subframes occurring at known, or signaled,
positions in the radio frame. Such subframes carrying at least
discovery signals are called discovery subframes in the
following.
So far, 3GPP RAN1#73 R1-132861 has agreed to study further the
following options for scheduling discovery signals: Type 1: A
discovery procedure where resources for discovery signal
transmission are allocated on a non-wireless device specific basis,
e.g., non-UE specific basis, Note: Resources may be for all
wireless devices or group of wireless devices. Type 2: A discovery
procedure where resources for discovery signal transmission are
allocated on a per wireless device specific basis. Type 2A:
Resources are allocated for each specific transmission instance of
discovery signals. Type 2B: Resources are semi-persistently
allocated for discovery signal transmission.
While type-1 and type-2 were defined, so far there is no agreement
about when to use which type.
Recently, D2D communications as an underlay to cellular networks
have been proposed as a means to take advantage of the proximity of
communicating wireless devices and, at the same time, to allow
wireless devices to operate in a controlled interference
environment. Typically, it is suggested that such D2D communication
shares the same spectrum as the cellular system, for example by
reserving some of the cellular uplink resources for D2D purposes.
Allocating dedicated spectrum for D2D purposes is a less likely
alternative, as spectrum is a scarce resource and, dynamic, sharing
between the D2D services and cellular services is more flexible and
provides higher spectrum efficiency.
SUMMARY
It is an object of embodiments herein to improve the performance in
a radio communications network by providing an improved way for a
network node to allocate radio resources to at least one wireless
device for D2D communications.
According to a first aspect of embodiments herein, the object is
achieved by a method performed by a network node. The method is for
adapting an allocation of radio resources to at least one wireless
device for D2D communications. The at least one wireless device is
located in a cell served by the network node. The network node
obtains a measurement of interference level on allocated D2D radio
resources to the at least one wireless device. The network node
adapts the allocation of radio resources for D2D communications,
based on the obtained measurement.
According to a second aspect of embodiments herein, the object is
achieved by a method performed by the wireless device. The method
is for adopting a reconfiguration of the allocation of radio
resources to the at least one wireless device for D2D
communications. The wireless device is located in the cell served
by the network node. The wireless device receives from the network
node the reconfiguration of the allocation of radio resources for
D2D communications. The reconfiguration is based on the measurement
of interference level on allocated D2D radio resources to the at
least one wireless device obtained by the network node. The
wireless device adopts the received reconfiguration of the
allocation of radio resources for D2D communications.
According to a third aspect of embodiments herein, the object is
achieved by the network node for adapting the allocation of radio
resources to the at least one wireless device for D2D
communications. The at least one wireless device is configured to
be located in the cell configured to be served by the network node.
The network node is configured to obtain the measurement of
interference level on the allocated D2D radio resources to the at
least one wireless device. The network node is further configured
to adapt the allocation of the radio resources for D2D
communications, based on the obtained measurement.
According to a fourth aspect of embodiments herein, the object is
achieved by the wireless device for adopting the reconfiguration of
the allocation of radio resources to the at least one wireless
device for D2D communications. The wireless device is configured to
be located in the cell configured to be served by the network node.
The wireless device is configured to receive from the network node
the reconfiguration of the allocation of radio resources for D2D
communications. The reconfiguration is based on the measurement of
interference level on allocated D2D radio resources to the at least
one wireless device configured to be obtained by the network node.
The wireless device is also configured to adopt the received
reconfiguration of the allocation of radio resources for D2D
communications.
According to a fifth aspect of embodiments herein, the object is
achieved by a computer program, comprising instructions which, when
executed on at least one processor, cause the at least one
processor to carry out the method performed by the network
node.
According to a sixth aspect of embodiments herein, the object is
achieved by a computer-readable storage medium, having stored
thereon the computer program, comprising instructions which, when
executed on at least one processor, cause the at least one
processor to carry out the method performed by the network
node.
According to a seventh aspect of embodiments herein, the object is
achieved by a computer program, comprising instructions which, when
executed on at least one processor, cause the at least one
processor to carry out the method performed by the wireless
device.
According to an eighth aspect of embodiments herein, the object is
achieved by a computer-readable storage medium, having stored
thereon the computer program, comprising instructions which, when
executed on at least one processor, cause the at least one
processor to carry out the method performed by the wireless
device.
By the network node obtaining the measurement of interference level
on the allocated D2D radio resources to the at least one wireless
device, it may be able to adapt the radio resources allocated for
D2D communications to the detected load on D2D resources. This
provides for a low complexity and low overhead method to optimize
spectrum efficiency. For example, if the usage of D2D
communications is low, not as many radio resources may be allocated
to D2D communications, and they may instead be used for cellular
communications, and vice versa.
Further advantages of some embodiments disclosed herein are
discussed below.
BRIEF DESCRIPTION OF THE DRAWINGS
Examples of embodiments herein are described in more detail with
reference to attached drawings in which:
FIG. 1 is a schematic block diagram illustrating embodiments in a
radio communications network, according to embodiments herein.
FIG. 2 is a flowchart depicting embodiments of a method in a
network node, according to embodiments herein.
FIG. 3 is schematic diagram illustrating FDM mapping of D2D
resources in selected subframes, according to embodiments
herein.
FIG. 4 is a flowchart depicting embodiments of a method in a
wireless device, according to embodiments herein.
FIG. 5 is a schematic block diagram illustrating embodiments of a
network node, according to embodiments herein.
FIG. 6 is a schematic block diagram illustrating embodiments of a
wireless device, according to embodiments herein.
DETAILED DESCRIPTION
As part of developing embodiments herein, one or more problems that
may be associated with use of at least some of the prior art
solutions, and that may addressed by embodiments herein will first
be identified and discussed.
When a wireless device is in Radio Resource Control (RRC)_CONNECTED
mode, the Evolved Universal Terrestrial Radio Access Network
(E-UTRAN) tracks the position of the wireless device at a cell
level, i.e. the E-UTRAN knows in which cell the wireless device is
located and thus which network node, e.g., eNB, the wireless device
is connected to. This means that the network node may determine the
amount of resources needed for various services and how to
prioritize among these.
When a wireless device is in RRC_IDLE mode, the position of the
wireless device may be tracked on Tracking Area (TA)-level.
Typically, a TA is made up of several cells. Each cell broadcasts
which TA it is part of and when a wireless device changes TA, i.e.,
when it moves into a cell in a new TA, the wireless device performs
a Tracking Area Update (TAU). If a wireless device moves between
cells of the same TA, no TAU is performed.
The TAU is a procedure performed between a wireless device and a
Core Network (CN), such as a Mobility Management Entity (MME) in
the CN. Thus, the network node has no knowledge of the number of
RRC_IDLE wireless devices in its cell. This means that the network
node cannot determine the amount of resources needed for the
RRC_IDLE wireless devices. As the design in LTE is for wireless
devices in RRC_IDLE to consume as little resources as possible,
this is typically not a problem. However, with the introduction of
D2D services, wireless devices in RRC_IDLE may perform D2D
Discovery or D2D Communication, which consumes resources for the
network node.
RRC_idle wireless devices may participate in D2D communication,
including transmission of direct signals/channels. The network node
is unaware of the number of camping RRC_idle wireless devices and
it is not even aware of how many of such wireless devices
participate to D2D. The network node is unable to optimize D2D
resource allocation without such load information.
Thus, with existing solutions, the network node is not able
establish to sufficiently well how many wireless devices are using
resources reserved for D2D in a cell.
Embodiments described herein have the advantage that the network
node may convey information about the load of the D2D resources in
a low complexity and low overhead method. In some embodiments, the
network node may measure the received, i.e., detected, energy on
the resources associated with D2D transmission and may adapt the
amount of resources allocated for D2D also based on such
measurement.
Embodiments will now be described more fully hereinafter with
reference to the accompanying drawings, in which examples of the
claimed subject matter are shown. The claimed subject matter may,
however, be embodied in many different forms and should not be
construed as limited to the embodiments set forth herein. Rather,
these embodiments are provided so that this disclosure will be
thorough and complete, and will fully convey the scope of the
claimed subject matter to those skilled in the art. It should also
be noted that these embodiments are not mutually exclusive.
Components from one embodiment may be tacitly assumed to be
present/used in another embodiment.
FIG. 1 depicts a radio communications network 100, sometimes also
referred to as a cellular radio system, cellular network or
wireless communications system, in which embodiments herein may be
implemented. The radio communications network 100 may for example
be a network such as a Long-Term Evolution (LTE), e.g. LTE
Frequency Division Duplex (FDD), LTE Time Division Duplex (TDD),
LTE Half-Duplex Frequency Division Duplex (HD-FDD), LTE operating
in an unlicensed band, Wideband Code Division Multiple Access
(WCDMA), Universal Terrestrial Radio Access (UTRA) TDD, Global
System for Mobile communications (GSM) network, GSM/Enhanced Data
Rate for GSM Evolution (EDGE) Radio Access Network (GERAN) network,
Ultra-Mobile Broadband (UMB), EDGE network, network comprising of
any combination of Radio Access Technologies (RATs) such as e.g.
Multi-Standard Radio (MSR) base stations, multi-RAT base stations
etc., any 3rd Generation Partnership Project (3GPP) cellular
network, WiFi networks, Worldwide Interoperability for Microwave
Access (WiMax), 5G system or any cellular network or system. Thus,
although terminology from 3GPP LTE may be used in this disclosure
to exemplify embodiments herein, this should not be seen as
limiting the scope of the embodiments herein to only the
aforementioned system.
The radio communications network 100 comprises a network node 111,
and neighbor network node 112, which is another network node that
is neighbor to network node 111. Each of the network node 111 and
the neighbor network node 112 may be, for example, base stations
such as e.g., an eNB, eNodeB, or a Home Node B, a Home eNode B,
femto Base Station, BS, pico BS or any other network unit capable
to serve a wireless device or a machine type communication device
in a radio communications network 100. In some particular
embodiments, the network node 111 and the neighbor network node 112
may be a stationary relay node or a mobile relay node.
The radio communications network 100 covers a geographical area
which is divided into cell areas, wherein each cell area is served
by a network node, although, one network node may serve one or
several cells. In the non-limiting example depicted in FIG. 1, the
network node 111 serves a first cell 121, also referred to herein
as the cell 121, and the neighbor network node 112 serves a second
cell 122. Each of the network node 111 and the neighbor network
node 112 may be of different classes, such as, e.g., macro eNodeB,
home eNodeB or pico base station, based on transmission power and
thereby also cell size. Typically, radio communications network 100
may comprise more cells similar to the first cell 121 and the
second cell 122, served by their respective network node. This is
not depicted in FIG. 1 for the sake of simplicity. Each of the
network node 111 and the neighbor network node 112 may support one
or several communication technologies, and its name may depend on
the technology and terminology used. In 3GPP LTE, the network node
111 and the neighbor network node 112, which may be referred to as
eNodeBs or even eNBs, may be directly connected to one or more core
networks 130. The network node 111 and the neighbor network node
112 may communicate with the one or more core networks 130 over a
first link 141 and over a second link 142, respectively. The
network node 111 may communicate with the neighbor network node 112
over a first link 150.
A number of wireless devices are located in the radio
communications network 100. In the example scenario of FIG. 1, only
two wireless devices are shown, a first wireless device 161, also
referred to herein as "the wireless device 161" or "one wireless
device 161", and a second wireless device 162. Each of the first
wireless device 161 and the second wireless device 162 is a
wireless communication device such as a UE, which is also known as
e.g., mobile terminal, wireless terminal, mobile station, mobile
telephone, and/or cellular telephone. Further examples of different
wireless devices include laptops with wireless capability, modems,
Personal Digital Assistants (PDA), or tablet computers, sometimes
referred to as a surf plates with wireless capability,
Machine-to-Machine (M2M) devices, devices equipped with a wireless
interface, such as a printer or a file storage device, Machine Type
Communication (MTC) devices such as sensors, just to mention some
examples. Each of the devices is wireless, i.e., it is enabled to
communicate, e.g., voice and/or data, wirelessly in the radio
communications network 100. The communication may be performed
e.g., between two devices, such as between the first wireless
device 161 and the second wireless device 162, as described above,
between a device and a regular telephone and/or between a device
and another entity, such as a server or any other radio network
unit capable of communicating over a radio link in the radio
communications network 100. The communication may be performed
e.g., via a RAN and possibly the one or more core networks 130
comprised within the radio communications network 100.
The first wireless device 161 is located within the cell 121. The
first wireless device 161 is configured to communicate within the
wireless communications system 100 via the network node 111 over a
first radio link 171 when the first wireless device 161 is present
in the cell 121 served by the network node 111.
In this example, the second wireless device 162 is also located
within the cell 121. However, in other embodiments, the second
wireless device 162 may be located within the radio coverage of the
first wireless device 161, in another cell which is adjacent to the
cell 121. When the second wireless device 162 is present in the
cell 121, it is configured to communicate within the radio
communications network 100 via the network node 111 over a radio
link such as e.g. a second radio link 172. When the second wireless
device 162 is present in another cell, e.g., cell 122, it is
configured to communicate within the radio communications network
100 via another network node serving the another cell, such as the
neighbor node 112 over another radio link similar the second radio
link 172.
The first wireless device 161 is capable of communicating with
other wireless devices using wireless D2D communication, such as
the second wireless device 162, over a D2D link 180. The second
wireless device 162 is capable of communicating with other wireless
devices using wireless D2D communication, such as the first
wireless device 161, over a D2D link such as the D2D link 180, in
the case of the second wireless device 162, or a similar D2D
link.
Embodiments of a method performed by the network node 111 for
adapting an allocation of radio resources to at least one wireless
device 161 for D2D communications, will now be described with
reference to the flowchart depicted in FIG. 2. As stated earlier,
the at least one wireless device 161 is located in the cell 121
served by the network node 111. The first wireless device 161 and
the network node 111 operate in the radio communications network
100.
The term "resource", as used herein, is intended to be interpreted
in a general way. It may indicate an arbitrary combination of
subcarriers, time slots, codes and spatial dimensions.
The allocation of radio resources to the at least one wireless
device 161 for D2D communications may be interpreted as the set of
resources for certain D2D operations by the at least one wireless
device 161, that have been configured, e.g., preconfigured, by the
network node 111. The radio resources comprised in the allocation
may be referred to herein as the allocated D2D radio resources to
the at least one wireless device 161. For example, this means that
the allocation of radio resources to at least one wireless device
161 for D2D communications may encompass different resources sets,
such as A+B+C+D, wherein, e.g. radio resource set A may be used by
the wireless device 161, and, e.g., radio resource set B may be
empty.
The network node 111 may configure these resources for D2D
operations in a wireless device-specific or non-wireless
device-specific fashion, e.g., in a wireless device 161-specific or
non-wireless device 161-specific fashion. The wireless device 161
may use non-wireless device 161-specific resources in a
contention-based fashion, possibly based on distributed resource
allocation algorithms.
In some embodiments, the wireless device 161 may be in idle mode,
such as in RRC_idle mode. It may be assumed that the wireless
device 161, even when it is RRC_idle, may be able to transmit D2D
signals in the pre-configured resources, where the
pre-configuration may be managed by the network node 111. The same
may apply, in general, to wireless devices such as wireless device
161, without an active network node connection. Such wireless
devices may be unable to communicate with the network node 111. The
resources may also be configured in a semi-static fashion using
System Information that the wireless devices in RRC_IDLE, such as
the wireless device 161 when in RRC_idle mode, may be obliged to
track.
RRC_connected wireless devices, such as wireless device 161 when in
RRC_connected mode, may, however, be assigned resources for
transmission directly by the network node 111.
FIG. 2 depicts a flowchart of the actions that are or may be
performed by the network node 111 in embodiments herein. In the
Figure, a box with dashed lines indicates that the action is
optional.
The method may comprise the following actions, which actions may as
well be carried out in another suitable order than that described
below. In some embodiments, all the actions may be carried out,
whereas in other embodiments only some action/s may be carried
out.
Action 201
In order for the network node 111 to optimize D2D resource
allocation according to the load of D2D resources, the network node
111 obtains a measurement of interference level on allocated D2D
radio resources to the at least one wireless device 161.
"A measurement" on allocated D2D radio resources to the at least
one wireless device 161 is understood herein as any one measurement
of the radio resources in the allocation of radio resources to at
least one wireless device 161 for D2D communications. These
resources, as stated earlier, may encompass different resources
sets, such as A+B+C+D, wherein, e.g. radio resource set A may be
used by the wireless device 161, and, e.g., radio resource set B
may be empty. Thus, the measurement, as understood herein, may
encompass any measurement of A+B+C+D, such as a measurement of A,
or a measurement of B. That is, for example, if the wireless device
161 uses resource set A, the network node 111 may obtain the
measurement on resource set B.
The measurement may comprise at least one energy measurement or at
least one signal detection on individual resources in order to
estimate a fraction of resources that is utilized for D2D in the
radio communications network 100.
In some embodiments, obtaining the energy measurement may comprise
measuring an energy level received on the considered resources.
Thus, in some embodiments, the measurement may comprise an energy
level received by the network node 111 or the wireless device 161
on the allocated D2D radio resources. In some embodiments, the
energy level may be a Reference Signal Received Power (RSRP).
In some embodiments, the measurement may comprise a signal detected
by the network node 111 or by the wireless device 161 in the
allocated D2D radio resources. The signal detected may comprise the
energy or intensity level associated to a certain specific signal,
e.g., a reference signal, is measured on the considered resources.
Additional or alternative measurements may be performed at higher
layers, including detection of Cyclic Redundancy Check (CRC) when
decoding the D2D messages.
In some embodiments, the obtaining the measurement may comprise
receiving a report from the wireless device 161 which report
indicates the energy level received by the wireless device 161 on
the allocated D2D radio resources, or the signal detected by the
wireless device 161 in the allocated D2D radio resources. This may
be implemented by, for example, receiving the report in a control
message from the wireless device 161.
In some of these embodiments, the network node 111 may first
configure the wireless device 161 to send to the network node 111
the report comprising the energy level received by the wireless
device 161 on the allocated D2D radio resources, or the signal
detected by the wireless device 161 in the allocated D2D radio
resources. This may be implemented by, for example, sending an RRC
message to the wireless device 161.
The measurement of interference according to any of the embodiments
herein, may result, in some embodiments, in a value or a range of
values corresponding to no interference, or negligible
interference, according to one or more determined thresholds. While
other values or range of values resulting from the measurement of
interference, may be considered to correspond to problematic
interference or different degrees of problematic interference.
At least for certain types of D2D communication, interference
sensing at the transmitter may not provide an accurate indication
of which resources are free from interference at the receiver/s.
However, under the assumption that the D2D interference load is
approximately constant over relatively large geographical areas,
e.g., the cell 121, interference sensing for traffic load
measurement may not necessarily need to be performed at the
transmitter, but it may be performed at any node, including the
network node 111.
Thus, in some embodiments, the obtaining the measurement may
comprise the network node 111 measuring the energy level received
on a number of allocated D2D radio resources, or detecting the
signal in the allocated D2D radio resources.
Action 202
Since not all the allocated D2D radio resources may actually be
utilized, the network node 111 may estimate a fraction of the
allocated D2D radio resources that is utilized for D2D
communication in the radio communications network 100, wherein the
network node 111 and the wireless device 161 operate. This action
may allow the network node 111 to assess if and how much the
allocation of radio resources to the at least one wireless device
161 for D2D communications may be changed, based on
interference.
Action 203
The network node 111 adapts the allocation of radio resources for
D2D communications, based on the obtained measurement.
In some embodiments, the adapting may comprise one of: increasing a
number of radio resources available for D2D traffic, and reducing
the number of radio resources available for D2D traffic.
Following the example provided earlier, if the wireless device 161
uses resource set A, and the network node 111 obtains a measurement
on resource set B, and finds out that B is empty, the network node
111 may allocate to A+B to the wireless device 161.
The network node 111 may need to perform a number of Radio Resource
Management (RRM) operations in order to perform efficient resource
allocation. In particular, the balance between allocated D2D
resources and cellular resources may be a function of the traffic
load and interference scenarios for respectively D2D and cellular
traffic, since D2D and cellular may share resources from the same
radio carrier.
Thus, in some embodiments, the adapting may also further comprise
one of: increasing a number of radio resources available for legacy
cellular traffic, and reducing the number of radio resources
available for legacy cellular traffic.
In some embodiments, a use case for D2D may be for Public Safety
users. A typical scenario may be to respond to a fire or a traffic
incident. Due to the very nature of these scenarios, they may not
be known in advance. Therefore, it may be of importance that the
RRM operations mentioned earlier, i.e. that the balancing of
resources between D2D and legacy cellular traffic, are performed
swiftly.
The network node 111, may take any of the following actions as a
way to increase the resources for legacy cellular traffic, although
the list is non-exhaustive: Assigning a new carrier Changing
various parameters related to scheduling Start scheduling users on
resources previously refrained from scheduling on Use a less robust
Modulation and Coding Scheme (MCS) Increasing carrier bandwidth
The network node 111, may take any of the following actions as a
way to decrease the resources for legacy cellular traffic, although
the list is non-exhaustive: Withdrawing a deployed carrier Changing
various parameters related to scheduling Stop schedule users on
resources previously scheduled on Use a more robust MCS Decreasing
carrier bandwidth
In some embodiments, the network node 111 may detect the fraction
of resources that are occupied, according to energy and/or signal
detection criteria, and adjust resource allocation accordingly.
Thus, in some embodiments, the adapting may be further based on the
estimated fraction, as described in action 202. That is, if the
fraction of resources used for D2D transmission over the total
amount of resources assigned for D2D transmission is below or above
certain thresholds, the network node 111 may reconfigure the D2D
resources in order to respectively reduce and increase the amount
of resources available for D2D transmission.
In any of the embodiments herein, the allocation of radio resources
to the at least one wireless device 161 may be for scheduling
discovery signals with at least one of the following types: a) Type
1, wherein radio resources for discovery signal transmission are
allocated on a non-wireless device specific basis, b) Type 2,
wherein radio resources for discovery signal transmission are
allocated on a wireless device specific basis, c) Type 2A, wherein
radio resources for discovery signal transmission are allocated for
each specific transmission instance of discovery signals, and d)
Type 2B, wherein radio resources for discovery signal transmission
are semi-persistently allocated for discovery signal
transmission.
Action 204
The network node 111 may signal to the wireless device 161 or the
neighbor network node 112 a reconfiguration of the allocation of
radio resources for D2D communications. The reconfiguration may be
based on the adapted allocation of radio resources for D2D
communications. The reconfiguration of D2D and cellular resources
may be signalled to the wireless device 161, as well as to other
wireless devices, by, e.g., using system information, e.g., when
the wireless device 161 is in idle mode, or dedicated RRC
communication, e.g., when the wireless device 161 is in
RRC_connected mode, PDCCH, ePDCCH, etc. . . . .
"A reconfiguration of the allocation of radio resources for D2D
communications" is understood herein as any one reconfiguration of
the allocation of radio resources to at least one wireless device
161 for D2D communications. These resources, as stated earlier, may
encompass different resources sets, such as A+B+C+D, wherein, e.g.
radio resource set A may be used by the wireless device 161, and,
e.g., radio resource set B may be empty. Thus, the reconfiguration,
as understood herein, may encompass any reconfiguration of any of
the group A+B+C+D, such as a reconfiguration of A, or a
reconfiguration of A+B+C+D. That is, for example, if the wireless
device 161 uses resource set A, the network node 111 may signal a
reconfiguration of A or a reconfiguration of A+B+C+D.
The network node 111 may communicate the resources reconfiguration
or information about D2D load measurements to neighbour network
nodes, such as the network node 112 e.g., by X2 or OAM. As stated
earlier, the neighbor network node 112 operates in the radio
communications network 100.
In the description herein, FDM mapping of the D2D resources in
selected subframes may be assumed, in a not limiting way, as shown
in FIG. 3. FIG. 3 illustrates FDM mapping of D2D transmissions,
where multiple discovery messages, i.e., beacons, are mapped on
different resources in the frequency domain, within the same radio
subframe. The vertical lines in the Figure mark the different
subframes. The horizontal axis indicates time and the vertical axis
represents the frequency domain. Additionally, some cellular
transmissions are shown and occur in other subframes, e.g., TDM
between D2D and cellular. Nevertheless, a fraction of the D2D
subframes can potentially be allocated to cellular transmission,
such that the resources assigned to D2D consist of a fraction of a
subframe. It is in general preferable to avoid sharing the same
resource between cellular and D2D in order to avoid uncontrollable
interference. However, most of the principles and techniques
described herein may be applied to different resources multiplexing
techniques, such as CDM and TDM.
In any of the embodiments described herein, certain D2D
signals/channels may have a broadcast nature and the position and
number of potential receivers may not be known or controlled by any
node prior to the actual transmission. In this case, the
transmitter wireless device, such as the wireless device 161,
should ideally choose resources that are not interfered at its
potential, i.e., unknown, receivers.
Other signals or messages may be unicast or groupcast, i.e., they
may target a limited number of receivers. In this case, the
interference scenario at the selected receivers may be possibly
conveyed to the transmitter wireless device, such as the wireless
device 161, in order to optimize resource allocation.
Embodiments of a method performed by the wireless device 161 for
adopting the reconfiguration of the allocation of radio resources
to the at least one wireless device 161 for D2D communications,
will now be described with reference to the flowchart depicted
depicted in FIG. 4. As stated earlier, the wireless device 161 is
located in the cell 121 served by the network node 111. The first
wireless device 161 and the network node 111 operate in the radio
communications network 100, as also stated earlier. In some
embodiments, the wireless device 161 may be in idle mode.
FIG. 4 depicts a flowchart of the actions that are or may be
performed by the first wireless device 161 in embodiments herein.
In the Figure, a box with dashed lines indicates that the action is
optional.
The method may comprise the following actions, which actions may as
well be carried out in another suitable order than that described
below. In some embodiments, all the actions may be carried out,
whereas in other embodiments only some action/s may be carried
out.
The detailed description of some of the following corresponds to
the same references provided above, in relation to the actions
described for the network node 111, and will thus not be repeated
here. For example, the term "resource", as used herein, may
indicate an arbitrary combination of subcarriers, time slots, codes
and spatial dimensions. As another example, the reconfiguration is
defined as described in action 204.
Action 401
As described earlier, in some embodiments, one or more D2D enabled
wireless devices 161 may measure the load experienced on D2D
resources and then report it to the network node 111, as will be
described in Action 402.
The wireless device 161 may receive the configuration from the
network node 111 to send to the network node 111 the report
comprising the measurement of interference level on allocated D2D
radio resources to the at least one wireless device 161. This may
be implemented by, for example, by receiving the RRC message from
the network node 111, described in Action 201.
Such reporting may be triggered or configured by the network node
111 in different ways. In some examples, the network node 111 may
configure the wireless devices 161 when it is far away from the
network node 111, or close to the edge of cell 221 to feedback
information regarding D2D load. This may be, e.g., because the
network node 111 may not be able to measure the D2D load
experienced by the wireless device 111 at the edge of cell 221.
The measurement performed by the wireless device 161 may take
similar forms as the measurement described for the network node 111
in action 201. That is, the measurement may comprise the measured
energy level received by the wireless device 161 on the allocated
D2D radio resources, or the signal detected by the wireless device
161 in the allocated D2D radio resources.
Thus, in some embodiments, the wireless device 131 may determine
the measurement of interference level by one of: measuring the
energy level received on the number of allocated D2D radio
resources, or detecting the signal described in action 201, e.g., a
reference signal, in the allocated D2D radio resources.
The wireless device 161 may measure the energy level received on
the number of allocated D2D radio resources, for example, by
estimating a signal power level associated to the number of
allocated D2D radio resources.
The wireless device 161 may detect the signal in the allocated D2D
radio resources, for example, by detecting an energy associated to
reference signals potentially transmitted by wireless devices on
those resources or by attempting detection of the transmissions
occurring over those resources.
Action 402
The wireless device 161 may send the report comprising the
measurement, as described in Action 201, to the network node 111.
This may be implemented by, for example, sending the report in the
control message to the network node 111, as also described in
action 201.
Action 403
The wireless device 161 receives the reconfiguration of the
allocation of radio resources for D2D communications from the
network node 111, as described in action 204. The reconfiguration
is based on the measurement of interference level on allocated D2D
radio resources to the at least one wireless device 161 obtained by
the network node 111.
In some embodiments, the measurement may comprise the energy level
received by the network node 111 or by the wireless device 161 on
the allocated D2D radio resources, or the signal detected by the
network node 111 or by the wireless device 161 in the allocated D2D
radio resources.
In some embodiments, the reconfiguration is further based on the
fraction of the allocated D2D radio resources that is utilized for
D2D communication in the radio communications network 100 wherein
the network node 111 and the wireless device 161 operate. In these
embodiments, the fraction may have been estimated by the network
node 111, as described in action 202.
Action 404
The wireless device 161 adopts the received reconfiguration of the
allocation of radio resources for D2D communications. This may be
implemented, for example, by restricting the resources used for D2D
communication to those configured by the network node 111.
In some embodiments, the adopting the received reconfiguration
comprises one of: increasing the number of radio resources
available for D2D traffic, and reducing the number of radio
resources available for D2D traffic.
In some embodiments, the adopting may also further comprise one of:
increasing the number of radio resources available for legacy
cellular traffic, and reducing the number of radio resources
available for legacy cellular traffic.
In any of the embodiments herein, the allocation of radio resources
to the at least one wireless device 161 may be for scheduling
discovery signals with at least one of the following types: a) Type
1, wherein radio resources for discovery signal transmission are
allocated on a non-wireless device specific basis, b) Type 2,
wherein radio resources for discovery signal transmission are
allocated on a wireless device specific basis, c) Type 2A, wherein
radio resources for discovery signal transmission are allocated for
each specific transmission instance of discovery signals, and d)
Type 2B, wherein radio resources for discovery signal transmission
are semi-persistently allocated for discovery signal
transmission.
Embodiments described herein may have the advantage of providing
different approaches for detection of the load on D2D resources by
the network node 111, including the case where the at least one D2D
wireless device 161 may not be connected to the network node
111.
To perform the method actions described above in relation to FIGS.
2-3, the network node 111 is configured for adapting the allocation
of radio resources to the at least one wireless device 161 for D2D
communications. The network node 111 comprises the following
arrangement depicted in FIG. 5. As stated earlier, the at least one
wireless device 161 is configured to be located in the cell 121
configured to be served by the network node 111. The wireless
device 161 and the network node 111 are configured to operate in
the radio communications network 100. The detailed description of
some of the following corresponds to the same references provided
above, in relation to the actions described for the network node
111, and will thus not be repeated here.
In some embodiments, the wireless device 161 is configured to be in
idle mode.
The network node 111 is configured to obtain the measurement of
interference level on the allocated D2D radio resources to the at
least one wireless device 161.
In some embodiments, this may be implemented by an obtaining module
501 comprised in the network node 111.
In some embodiments, the measurement comprises the energy level
configured to be received by the network node 111 or the wireless
device 161 on the allocated D2D radio resources, or the signal
configured to be detected by the network node 111 or by the
wireless device 161 in the allocated D2D radio resources.
In some embodiments to obtain the measurement comprises: to measure
the energy level received on the number of allocated D2D radio
resources, or to detect the signal in the allocated D2D radio
resources. This may also be implemented by the obtaining module
501.
In some embodiments, to obtain the measurement comprises to receive
the report from the wireless device 161 which report indicates the
energy level received by the wireless device 161 on the allocated
D2D radio resources, or the signal detected by the wireless device
161 in the allocated D2D radio resources. This may also be
implemented by the obtaining module 501.
In some embodiments, the allocation of radio resources to the at
least one wireless device 161 is for scheduling discovery signals
with at least one of the following types: a) Type 1, wherein radio
resources for discovery signal transmission are allocated on a
non-wireless device specific basis, b) Type 2, wherein radio
resources for discovery signal transmission are allocated on a
wireless device specific basis, c) Type 2A, wherein radio resources
for discovery signal transmission are allocated for each specific
transmission instance of discovery signals, and d) Type 2B, wherein
radio resources for discovery signal transmission are
semi-persistently allocated for discovery signal transmission.
The network node 111 is configured to adapt the allocation of radio
resources for D2D communications, based on the obtained
measurement.
This may be implemented by an adapting module 502 comprised in the
network node 111.
In some embodiments, to adapt comprises one of: to increase the
number of radio resources available for D2D traffic, and to reduce
the number of radio resources available for D2D traffic.
In some embodiments, to adapt comprises one of: to increase the
number of radio resources available for legacy cellular traffic,
and to reduce the number of radio resources available for legacy
cellular traffic.
In some embodiments, the network node 111 may be further configured
to estimate the fraction of the allocated D2D radio resources that
is utilized for D2D communication in the radio communications
network 100 wherein the network node 111 and the wireless device
161 are configured to operate.
This may be implemented by an estimating module 503 comprised in
the network node 111.
In some embodiments, the network node 111 may be further configured
to adapt based on the estimated fraction.
In some embodiments, the network node 111 may be further configured
to signal to the wireless device 161 or the neighbor network node
112 the reconfiguration of the allocation of the radio resources
for D2D communications, which reconfiguration is based on the
adapted allocation of radio resources for D2D communications. The
neighbor network node 112 is configured to operate in the wireless
communications network 1.
This may be implemented by a signaling module 504 comprised in the
network node 111.
In some embodiments, the network node 111 may be further configured
to configure the wireless device 161 to send to the network node
111 the report comprising the energy level received by the wireless
device 161 on the allocated D2D radio resources, or the signal
detected by the wireless device 161 in the allocated D2D radio
resources
This may be implemented by a configuring module 505 comprised in
the network node 111.
The embodiments herein for adapting the allocation of radio
resources to the at least one wireless device 161 for D2D
communications may be implemented through one or more processors,
such as the processing module 506 in the network node 111 depicted
in FIG. 5, together with computer program code for performing the
functions and actions of the embodiments herein. The program code
mentioned above may also be provided as a computer program product,
for instance in the form of a data carrier carrying computer
program code for performing the embodiments herein when being
loaded into the in the network node 111. One such carrier may be in
the form of a CD ROM disc. It may be however feasible with other
data carriers such as a memory stick. The computer program code may
furthermore be provided as pure program code on a server and
downloaded to the network node 111.
The network node 111 may further comprise a memory module 507
comprising one or more memory units. The memory module 507 may be
arranged to be used to store data in relation to applications to
perform the methods herein when being executed in the network node
111. Memory module 507 may be in communication with the processing
module 506. Any of the other information processed by the
processing module 506 may also be stored in the memory module
507.
In some embodiments, information may be received from, e.g., the
wireless device 161, through a receiving port 508. In some
embodiments, the receiving port 508 may be, for example, connected
to one or more antennas in the network node 111. In other
embodiments, the network node 111 may receive information from
another structure in the radio communications network 100 through
the receiving port 508. Since the receiving port 508 may be in
communication with the processing module 506, the receiving port
508 may then send the received information to the processing module
506. The receiving port 508 may also be configured to receive other
information.
The information processed by the processing module 506 in relation
to the embodiments of the method herein may be stored in the memory
module 507 which, may be in communication with the processing
module 506, as stated earlier, and with the receiving port 508.
The processing module 506 may be further configured to transmit or
send information to e.g., the wireless device 161, through a
sending port 509, which may be in communication with the processing
module 506, and the memory module 507.
Those skilled in the art will also appreciate that the different
modules 501-505 described above may refer to a combination of
analog and digital modules, and/or one or more processors
configured with software and/or firmware, e.g., stored in memory,
that, when executed by the one or more processors such as the
processing module 506, perform as described above. One or more of
these processors, as well as the other digital hardware, may be
included in a single Application-Specific Integrated Circuit
(ASIC), or several processors and various digital hardware may be
distributed among several separate components, whether individually
packaged or assembled into a System-on-a-Chip (SoC).
Also, in some embodiments, the different modules 501-505 described
above may be implemented as one or more applications running on one
or more processors such as the processing module 506.
Thus, the methods according to the embodiments described herein for
the network node 111 are respectively implemented by means of a
computer program product, comprising instructions, i.e., software
code portions, which, when executed on at least one processor,
cause the at least one processor to carry out the actions described
herein, as performed by the network node 111. The computer program
product may be stored on a computer-readable storage medium. The
computer-readable storage medium, having stored thereon the
computer program, may comprise instructions which, when executed on
at least one processor, cause the at least one processor to carry
out the actions described herein, as performed by the network node
111. In some embodiments, the computer-readable storage medium may
be a non-transitory computer-readable storage medium, such as a CD
ROM disc, or a memory stick.
To perform the method actions described above in relation to FIG.
4, the wireless device 161 is configured for adopting the
reconfiguration of the allocation of radio resources to the at
least one wireless device 161 for D2D communications. The wireless
device 161 comprises the following arrangement depicted in FIG. 6.
The wireless device 161 is configured to be located in the cell
121, which is configured to be served by the network node 111. The
wireless device 161 and the network node 111 are configured to
operate in the radio communications network 100. The detailed
description of some of the following corresponds to the same
references provided above, in relation to the actions described for
the wireless device 161, and will thus not be repeated here.
In some embodiments, the wireless device 161 is configured to be in
idle mode.
The wireless device 161 is configured to receive from the network
node 111 the reconfiguration of the allocation of radio resources
for D2D communications, the reconfiguration being based on the
measurement of interference level on allocated D2D radio resources
to the at least one wireless device 161 configured to be obtained
by the network node 111.
In some embodiments, this may be implemented by a receiving module
601 comprised in the wireless device 161.
In some embodiments, the measurement comprises the energy level
configured to be received by the network node 111 or by the
wireless device 161 on the allocated D2D radio resources, or the
signal configured to be detected by the network node 111 or by the
wireless device 161 in the allocated D2D radio resources.
In some embodiments, the reconfiguration is further based on the
fraction of the allocated D2D radio resources that is utilized for
D2D communication in the radio communications network 100 wherein
the network node 111 and the wireless device 161 are configured to
operate, the fraction being configured to be estimated by the
network node 111.
In some embodiments, the allocation of radio resources to the at
least one wireless device 161 is for scheduling discovery signals
with at least one of the following types: a) Type 1, wherein radio
resources for discovery signal transmission are allocated on a
non-wireless device specific basis, b) Type 2, wherein radio
resources for discovery signal transmission are allocated on a
wireless device specific basis, c) Type 2A, wherein radio resources
for discovery signal transmission are allocated for each specific
transmission instance of discovery signals, and d) Type 2B, wherein
radio resources for discovery signal transmission are
semi-persistently allocated for discovery signal transmission.
In some embodiments, the wireless device 161 may be further
configured to receive the configuration from the network node 111
to send to the network node 111 the report comprising the
measurement of interference level on allocated D2D radio resources
to the at least one wireless device 161, the measurement comprising
the measured energy level received by the wireless device 161 on
the allocated D2D radio resources, or the signal detected by the
wireless device 161 in the allocated D2D radio resources
This may also be implemented by the receiving module 601.
The wireless device 161 is also configured to adopt the received
reconfiguration of the allocation of radio resources for D2D
communications.
This may be implemented by an adopting module 602 comprised in the
wireless device 161.
In some embodiments, to adopt the received reconfiguration
comprises one of: to increase the number of radio resources
available for D2D traffic, and to reduce the number of radio
resources available for D2D traffic.
In some embodiments, to adopt the received reconfiguration
comprises one of: to increase the number of radio resources
available for legacy cellular traffic, and to reduce the number of
radio resources available for legacy cellular traffic.
In some embodiments, the wireless device 161 may be further
configured to determine the measurement of interference level by
being configured to one of: to measure the energy level configured
to be received by the wireless device 161 on the number of
allocated D2D radio resources, or to detect the signal in the
allocated D2D radio resources.
This may be implemented by a determining module 603 comprised in
the wireless device 161.
In some embodiments, the wireless device 161 may be further
configured to send the report comprising the measurement of
interference level on allocated D2D radio resources to the at least
one wireless device 161 to the network node 111, the measurement
comprising the measured energy level received by the wireless
device 161 on the allocated D2D radio resources, or the signal
detected by the wireless device 161 in the allocated D2D radio
resources.
This may be implemented by a sending module 604 comprised in the
wireless device 161.
The embodiments herein for adopting the reconfiguration of the
allocation of radio resources to the at least one wireless device
161 for D2D communications may be implemented through one or more
processors, such as the processing module 605 in the wireless
device 161 depicted in FIG. 6, together with computer program code
for performing the functions and actions of the embodiments herein.
The program code mentioned above may also be provided as a computer
program product, for instance in the form of a data carrier
carrying computer program code for performing the embodiments
herein when being loaded into the in the wireless device 161. One
such carrier may be in the form of a CD ROM disc. It may be however
feasible with other data carriers such as a memory stick. The
computer program code may furthermore be provided as pure program
code on a server and downloaded to the wireless device 161.
The wireless device 161 may further comprise a memory module 606
comprising one or more memory units. The memory module 606 may be
arranged to be used to store data in relation to applications to
perform the methods herein when being executed in the wireless
device 161. Memory module 606 may be in communication with the
processing module 605. Any of the other information processed by
the processing module 605 may also be stored in the memory module
606.
In some embodiments, information may be received from, e.g., the
network node 111, through a receiving port 607. In some
embodiments, the receiving port 607 may be, for example, connected
to the one or more antennas in the wireless device 161. In other
embodiments, the wireless device 161 may receive information from
another structure in the radio communications network 100 through
the receiving port 607. Since the receiving port 607 may be in
communication with the processing module 605, the receiving port
607 may then send the received information to the processing module
605. The receiving port 607 may also be configured to receive other
information.
The information processed by the processing module 605 in relation
to the embodiments of method herein may be stored in the memory
module 606 which, as stated earlier, may be in communication with
the processing module 605 and the receiving port 607.
The processing module 605 may be further configured to transmit or
send information to e.g., the network node 111, through a sending
port 608, which may be in communication with the processing module
605, and the memory module 606.
Those skilled in the art will also appreciate that the different
modules 601-604 described above may refer to a combination of
analog and digital modules, and/or one or more processors
configured with software and/or firmware, e.g., stored in memory,
that, when executed by the one or more processors such as the
processing module 605, perform as described above. One or more of
these processors, as well as the other digital hardware, may be
included in a single Application-Specific Integrated Circuit
(ASIC), or several processors and various digital hardware may be
distributed among several separate components, whether individually
packaged or assembled into a System-on-a-Chip (SoC).
Also, in some embodiments, the different modules 601-604 described
above may be implemented as one or more applications running on one
or more processors such as the processing module 605.
Thus, the methods according to the embodiments described herein for
the wireless device 161 are respectively implemented by means of a
computer program product, comprising instructions, i.e., software
code portions, which, when executed on at least one processor,
cause the at least one processor to carry out the actions described
herein, as performed by the wireless device 161. The computer
program product may be stored on a computer-readable storage
medium. The computer-readable storage medium, having stored thereon
the computer program, may comprise instructions which, when
executed on at least one processor, cause the at least one
processor to carry out the actions described herein, as performed
by the wireless device 161. In some embodiments, the
computer-readable storage medium may be a non-transitory
computer-readable storage medium, such as a CD ROM disc, or a
memory stick.
When using the word "comprise" or "comprising" it shall be
interpreted as non-limiting, i.e. meaning "consist at least
of".
The modules described may be for performing any of the pertinent
embodiments described.
The embodiments herein are not limited to the above described
preferred embodiments. Various alternatives, modifications and
equivalents may be used. Therefore, the above embodiments should
not be taken as limiting the scope of the invention.
ABBREVIATIONS
CDM Code division multiplexing
CH Cluster head
CRC Cyclic Redundancy Check
D2D Device-to-Device
eNB E-UTRAN Node B
eNB evolved Node B
ePDCCH evolved PDCCH
FDM Frequency Division Multiplex
LTE Long Term Evolution
MCS Modulation and Coding Scheme
NW Network
OAM Operation and Maintenance
PDCCH Physical Downlink Control Channel
PRB Physical Resource Block
RAN Radio Access Network
RRC Radio Resource Control
RRM Radio Resource Management
TA Tracking Area
TAU Tracking Area Update
TDM Time Division Multiplexing
UTRAN Universal Terrestrial Radio Access Network
* * * * *